Anyway, I want to do an SBR build with all the evil features. What preban lower should I go with? I'm planning on a Noveske 10.5" upper, will an "older" Colt lower work? I've seen Sporter lowers on the EE, will this work for a carbine/SBR build? Are there any drawbacks? What should I expect to pay for a preban Colt lower? Will most of the newer stocks mate up with an older lower?

I'm not 100% set on Colt, but if I am going to register an SBR, I want to pick a quality lower to do it with.